Motor operated spray device



Oct. 6, 1953 F. M. DUNCAN 2,654,636

MOTOR OPERATED SPRAY DEVICE Filed Aug. 17, 1949 Patented Oct. 6, 1953MOTOR OPERATED SPRAY DEVICE Forrest M. Duncan, Long Island City, N. Y.,as-

signor, by mesne assignments, to Champion Implements Corporation, NewYork, N. Y., a

corporation of New York Application August 17, 1949, Serial No. 110,778

Claims.

The present invention is directed to equipment for spraying variousliquids such as paints and lacquers, and commonly known as a spray gun.

Devices of this character have been known for some time and usually haveconsisted of a compressor unit with a tank for compressed air, with aspray apparatus including a nozzle whereby the compressed air forces theliquid through the nozzle to form a spray. Such apparatus is quite bulkyand can be used only where a large 7 amount of work is to be done orwhere continuous application of the device takes place. While it may beportable, it requires several men for transportation, and usually inconjunction with a vehicle.

It has also been proposed to provide equipment which is readily portableand which may be readily handled by the operator. For instance, in onetype there was provided a magnetic motor with a pivoted armatureoperating a pump unit. Said unit was inserted into a container of theliquid and when the motor was operated, the liquid was sprayed. However,this type of equipment had a number of disadvantages in that it wasunbalanced and was difiicult for the operator to hold with one hand. Thepump arrangement being in the liquid soon became caked by the solidmaterial in the liquid and ceased to function. It was most difficult todisassemble the device for the purpose of cleaning and the device wasrelatively complicated and expensive in construction.

The present invention is intended and adapted to overcome thedifliculties and disadvantages inherent in prior devices of the typedescribed, it being among the objects of the present invention toprovide a spray gun which is simple in construction, which may betransported readily and which is highly effective in operation.

It is also among the objects of the present invention to provide astructure of spray gun which may be readily disassembled for cleaning orreplacement purposes without the necessity of special tools or specialskill on the part of the operator.

It is further among the objects of the present invention to provide aspray gun of the type described wherein maximum eifectiveness of thepower in the electromagnetic motor is obtained so that a steady streamof liquid may be obtained.

In practicing the present invention, there is provided a hollow bodywhich is usually rectangular in cross-section and in which anelectromagnet is held. The poles of the magnet extend rearwardlyadjacent to a vertically placed armature which is preferably not pivotedbut rests upon a ledge in the bottom of the hollow member so that it isentirely free to move and thus to develop the maximum power of themotor.

Extending rearwardly from the bottom of the hollow body is a hollowhandle in which is placed a suitable switch for operation of the motor.Electrical connections from a source of current enter the lower end ofthe handle and pass into the hollow body being connected to the motor. Atrigger operating device for the switch is pivoted at the lower frontend of the body so that the pressure of a finger may close the switch tooperate the motor, there being provided a spring for retracting thetrigger when pressure is released.

Extending forwardly from the top of the hollow body is a barrelcontaining the operating elements. Within the barrel is fixed acylindrical elongated bearing through which a push rod for a piston isintended to operate horizontally. The upper end of the armature contactsthe rear end of the push rod for the piston during the operationthereof. A suitable spring connected to the piston retracts itrearwardly. In the front of a barrel is a sleeve having a centralopening and a valve seat on which a spring pressed ball is adapted toseat. A transverse opening in the sleeve behind the seat allows liquidto be drawn into the same to be ejected past the seat. A nozzle embracesthe forward end of the sleeve and is threaded into the front end of thebarrel.

In the accompanying drawing constituting a part hereof, and in whichlike reference characters indicate like parts,

Fig. 1 is a side elevational view of a spray gun made in accordance withthe present invention, some parts being cut away for clearness;

Fig. 2 is a fragmentary front elevational view of a spray gun shown inFig. 1;

Fig. 3 is a vertical cross-sectional view thereof taken along the line3-3 of Fig. 2 and Fig. 4 is a fragmentary, vertical cross-sectional viewof a modified form of a spray gun.

Hollow body I which is roughly rectangular in cross-section is providedwith a cover 2 held by screws 3. An electromagnet 4 within body I haspoles 5 extending rearwardly, as shown in Figs. 1 and 3. A ledge 6 inthe bottom of body I provides means for a vertically placed armature Ito rest when the device is not in operation. An overhanging portion 8 atthe top of body 1 just above armature 1 provides a stop for limiting themotion of the upper end 9 of the armature. An adjustable set screw l0allows adjustment of 3 the length of horizontal movement of armature I.Bumper I in the inner end of screw I0 is adapted to absorb the shock ofthe impact of armature 9 in its movements.

At the lower end of body I and integral thereunder is a rearwardlyextending handle II within which the switch I2 is held. A cover .2 whichmay beintegral with cover 2 is held in position on the handle by screws3'. Blade I3- of switch I2 has a pin I4 extending outwardly from the topof handle II. Wires I5 extending from a source of current pass into thelower end of the handle through an opening (not shown) and are connectedto switch I2 and magnet-4. A trigger I6 ispivoted at H to the lowerfront endlof body =I and is provided at the lower end with a finger gripI8.

Extending forwardly from the top of body I is a barrel l9 having a finintegral therewith, the latter being formed with hook 2! providing meansfor hanging the device from a suitable support. The position of hook 21is such that When the assembly is made, it is'hung at approximatelythecenter of gravity thereof either when not in operation or evenwhen inuse.

The barrel has a horizontalbore 22 at the rear portion thereof withashoulder '23 at an intermediate portion so that bore 24 in the front ofthe barrel is of larger diameterthan bore 22. An elongated cylindricalbearing-member -25 orpush rod guide .is fixed 1into bore22. A push rod26contacts apiston 26and fits snugly in the bearing for reciprocationtherein. A coil spring 21 surrounds the rear of piston 26 and retractsthe same after actuation by armature I.

A sleeve. 28in bore 24contacts soft-metal washer 29 at shoulder 23. Ithas a central bore or cylinder .30 witha transverse opening 3Icommunicating with an external groove 32 on the face thereof. Front endof piston 26 is slidable in the cylinder past opening I The front ofbore .30 is enlarged :as shown at 33, the junctionforming.a-shouldcr 34constituting a'valve seat. Ball .35 biased rearwardly by coil spring 3.6fits on seat 34. Nozzle .31 having a jet 38 in a. central portionthereof-and ahollow body portion is adapted to embrace the front end 39of sleeve 28 and.forms a stop for the end of spring :36. Nozzle .31 isexternally threaded and fits into cooperating .threadsat the .forwardend of barrel .I9, A softmetal .washer provides a seal at thejunction-of nozzle 3 'I-and sleeve28.

A downwardly extending tube 40 is fitted into screw M which isthreadedat 42 into the' unclerside of barrel I9. Space 43 above tube '40communicates with groove 232. Cap 44 which is internally threaded isunited with barrel .I9 and pipe 40 held .in position as shown in Fig. 3by screw 4|. A container -45 such ,as a can or jar having the neckexternally threaded and carrying the liquid to be sprayed is threadedinto cap 44.

In the operation of the device the liquid is placed in container whichis screwed into cap 44. Wires .I5 are connected to a sourceof currentand the operatorgrasps handle 12 with his finger on grip I8, Uponpressing the grip, the circuit is closed through switch.l2, causingrapid shifting of armature 'I from leftto right. There is hampering ofthe movement because the armature in effect floats in the spaceitoccupies. At each stroke to the right, it impinges on 2626, moving itforward-and causingliquid in thebore to be ejected past ball and out ofnozzle 38. Then armature .I is retracted by the force of spring 21 andball 35 is seated by spring35.

stream is obtained.

'When it is desired to clean or repair the device, it is merelynecessary to unscrew nozzle 31, whereby the ball 35 and spring 36 may beremoved by shaking sleeve 28 which is also readily removable. "Piston'26and spring 21 may be removed by turning the front of barrel I9downwardly and gently shaking the gun, whereby the piston 26 and itsattached spring 21 will fall out. For

cleaning'tube lfl and associated parts, it is merely necessary to removescrew M. A drain 46 allows liquid from bore 22 to flow back intocontainer 45.

In Fig. 4, there is shown a modification in which tube '48 is fixed intoopening 3| of sleeve 28. To permit ready'removalof the sleeve andattached tube from the spray gun, avertical slot 41 is formed in thelower portion of the front end of barrel I9. After the removal of cap 44and nozzle 31, sleeve 28 and tube 40 may :be slipped out of the end ofthe gun.

Although the'invention has been described setting forth a singlespecific embodiment-thereof, various changes in the details ofconstruction may be made within the :principles herein set forth. Theinvention is, therefore, to be broadly construed and not to be limitedexcept by the claims appended hereto.

I claim:

1. A spray gun comprising'a hollow body, an electromagnet therein, anarmature adjacent the rear of said magnet and extending upwardly, ahandle extending from the lower portion of said body, a switch in saidhandle, a trigger'for manually operating said switch, electricalconnections between said switch, magnet and :a source of electricity, abarrel extending horizontally from the'top 'of said .body in alinementwith the upper end of said armature and above the top of said magnet, apiston therein, said armature adapted to :contact said piston, :rneanssecured to the lower side of the front .portion of said barrel forholding a depending container, and means associated with said pistonforspraying fiuid'at the outer end of said barrel.

2. A spray gun comprising a hollow .body,.an electromagnet therein,anarmature adjacent the rear of said magnet and extending upwardly, :ahandle extending from thelower portion of said body, aswitch in saidhandle, a trigger for manually operating saidswitch pivoted .at thelower portion of said body, electrical connections between said switch,magnet and a source of electricity, a barrel extending horizontally fromthe top of said body-in alinement-with the upper end of said armatureand above the top of said magnet, a piston, means secured to the lowerside of the front portion of said barrel for'holding a dependingcontainer therein, said arma ture adapted to contactsaid piston, andmeans associated with said piston for spraying fluid at the outer end ofsaid barrel.

3. A spray gun comprising a hollow body, an electromagnet therein,.anarmatureadjacent the rear of said magnet and extending upwardly, a ledgein said body on which said armature lies, a handle :extending from thelower portion of said body, a switch in said handle, a trigger formanually -.operating said switch, electrical connections between saidswitch, magnet and a source of electricity, a barrel extendinghorizontally from the top of said body in alinement with the upper endof said armature and above the top of said magnet, a piston, meanssecured to the lower side of the front portion of said barrel forholding a depending container therein, said armature adapted to contactsaid piston, and means associated with said piston for spraying fluid atthe outer end of said barrel.

4. A spray gun comprising a hollow body, an electromagnet therein, thepoles of said magnet extending horizontally, an armature adjacent therear of said magnet and extending upwardly, a handle extending from thelower portion of said body, a switch in said handle, a trigger formanually operating said switch, electrical connections between saidswitch, magnet and a source of electricity, a barrel extendinghorizontally from the top of said body in alinement with the upper endof said armature and above the top of said magnet, a piston, meanssecured to the lower side of the front portion of said barrel forholding a depending container therein, said armature adapted to contactsaid piston, and means associated with said piston for spraying fluid atthe outer end of said barrel.

5. In a spray gun, a barrel, a piston therein, a nozzle at one end andmeans for actuating said piston at the other end thereof, a removablesleeve having a valve seat therein in said barrel adjacent said nozzle,a ball valve contacting said seat, a spring in said sleeve bearing onsaid valve, said nozzle having a hollowed portion threaded into saidbarrel, the outer end of said sleeve fitted in said hollow, washers atboth ends of said sleeve, one of said Washers contacting a shoulderedportion of said barrel and the other washer contacting the inner end ofsaid nozzle, an opening in the face of said sleeve rearwardly of saidvalve and a tube attached to said barrel in communication with saidopening, the free end of said tube adapted to be immersed in fluid to besprayed.

6. In a spray gun, a barrel, a piston therein, a nozzle at one end andmeans for actuating said piston at the other end thereof, a removablesleeve having a valve seat therein in said barrel adjacent said nozzle,a ball valve contacting said seat, a spring in said sleeve bearing onsaid valve, an opening in the face of said sleeve rearwardly of saidvalve and a circumferential groove in said sleeve at said opening, atube attached to said barrel in communication with said opening, thefree end of said tube adapted to be immersed in fluid to be sprayed.

7. In a spray gun, a barrel, a piston therein, a nozzle at one end andmeans for actuating said piston at the other end thereof, a removablesleeve having a valve seat therein in said barrel adjacent said nozzle,a ball valve contacting said seat, a spring in said sleeve bearing onsaid valve, an opening in the face of said sleeve rearwardly of saidvalve and a tube attached to said barrel in communication with saidopening, the free end of said tube adapted to be immersed in fluid to besprayed, an elongated bearing fixed in the central portion of saidbarrel, a pushrod fitted therein and extending from both ends, saidpushrod having one end in contact with one end of said piston.

8. In a spray gun, a barrel, a piston therein, a nozzle at one end andmeans for actuating said piston at the other end thereof, a removablesleeve of uniform diameter in which said piston slides, an enlargementat the front of said sleeve, said enlargement having a valve seattherein in said barrel adjacent said nozzle, a ball valve contactingsaid seat, a spring in said sleeve bearing on said valve, an opening inthe face of said sleeve rearwardly of said valve and a tube attached tosaid barrel in communication with said opening, the free end of saidtube adapted to be immersed in fluid to be sprayed, an elongated bearingfixed in the central portion of said barrel and extending rearwardlytherefrom, a separate pushrod for a pushrod fitted therein and extendingfrom both ends, said pushrod having one end in contact with one end ofsaid piston, and a spring at the nozzle end of said piston biasing thesame rearwardly, a body rearwardly of said barrel into which saidbearing extends, a magnet below said bearing in said body, ahorizontally movable armature rearwardly of said magnet and extendingabove the same, said piston being in axial alinement with the top ofsaid armature.

9. A spray gun comprising a hollow body, an electromagnet therein, anarmature adjacent the rear of said magnet and extending upwardly, ahandle extending from the lower portion of said body, a switch in saidhandle, a trigger for manually operating said switch, electricalconnections between said switch, magnet and a source of electricity, abarrel extending horizontally from the top of said body in alinementwith the upper end of said armature and above the top of said magnet, apiston therein, a pushrod in axial alinement with said piston, meanssecured to the lower side of the front portion of said barrel forholding a depending container, said armature adapted to contact saidrod, and means associated with said piston for spraying fluid at theouter end of said barrel.

10. In a spray gun, a barrel, a piston therein, a nozzle at one end andmeans for actuating said piston at the other end thereof, a removablesleeve having a valve seat therein in said barrel adjacent said nozzle,a ball valve contacting said seat, a spring in said sleeve bearing onsaid valve, an opening in the face of said sleeve rearwardly of saidvalve and a tube fixed in said opening, the free end of said tubeadapted to be immersed in fluid to be sprayed, said barrel having a slotextending from the front end thereof to said tube, said slot adapted topermit the removal of said sleeve and tube as a unit from said barrel.

FORREST M. DUNCAN.

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